From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boris Brezillon Subject: Re: [PATCH 4/6] clk: at91: clk-generated: create function to find best_diff Date: Mon, 3 Jul 2017 16:02:45 +0200 Message-ID: <20170703160245.1481942e@bbrezillon> References: <20170623090059.8371-1-quentin.schulz@free-electrons.com> <20170623090059.8371-5-quentin.schulz@free-electrons.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170623090059.8371-5-quentin.schulz@free-electrons.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Quentin Schulz Cc: mark.rutland@arm.com, devicetree@vger.kernel.org, alsa-devel@alsa-project.org, thomas.petazzoni@free-electrons.com, lgirdwood@gmail.com, linux-kernel@vger.kernel.org, mturquette@baylibre.com, tiwai@suse.com, sboyd@codeaurora.org, nicolas.ferre@microchip.com, linux@armlinux.org.uk, robh+dt@kernel.org, alexandre.belloni@free-electrons.com, broonie@kernel.org, linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org On Fri, 23 Jun 2017 11:00:57 +0200 Quentin Schulz wrote: > The way to find the best_diff and do the appropriate process afterwards > can be re-used. > > This patch prepares the driver for an upcoming patch that will allow > clk_generated to determine the rate of the audio_pll. > > Signed-off-by: Quentin Schulz Acked-by: Boris Brezillon > --- > drivers/clk/at91/clk-generated.c | 41 ++++++++++++++++++++++++++-------------- > 1 file changed, 27 insertions(+), 14 deletions(-) > > diff --git a/drivers/clk/at91/clk-generated.c b/drivers/clk/at91/clk-generated.c > index dab7002937e6..6530a2e7e84d 100644 > --- a/drivers/clk/at91/clk-generated.c > +++ b/drivers/clk/at91/clk-generated.c > @@ -99,15 +99,36 @@ clk_generated_recalc_rate(struct clk_hw *hw, > return DIV_ROUND_CLOSEST(parent_rate, gck->gckdiv + 1); > } > > +static void clk_generated_best_diff(struct clk_rate_request *req, > + struct clk_hw *parent, > + unsigned long parent_rate, u32 div, > + int *best_diff, long *best_rate) > +{ > + unsigned long tmp_rate; > + int tmp_diff; > + > + if (!div) > + tmp_rate = parent_rate; > + else > + tmp_rate = parent_rate / div; > + tmp_diff = abs(req->rate - tmp_rate); > + > + if (*best_diff < 0 || *best_diff > tmp_diff) { > + *best_rate = tmp_rate; > + *best_diff = tmp_diff; > + req->best_parent_rate = parent_rate; > + req->best_parent_hw = parent; > + } > +} > + > static int clk_generated_determine_rate(struct clk_hw *hw, > struct clk_rate_request *req) > { > struct clk_generated *gck = to_clk_generated(hw); > struct clk_hw *parent = NULL; > long best_rate = -EINVAL; > - unsigned long tmp_rate, min_rate; > + unsigned long min_rate; > int best_diff = -1; > - int tmp_diff; > int i; > > for (i = 0; i < clk_hw_get_num_parents(hw); i++) { > @@ -125,18 +146,10 @@ static int clk_generated_determine_rate(struct clk_hw *hw, > continue; > > div = DIV_ROUND_CLOSEST(parent_rate, req->rate); > - if (!div) > - tmp_rate = parent_rate; > - else > - tmp_rate = parent_rate / div; > - tmp_diff = abs(req->rate - tmp_rate); > - > - if (best_diff < 0 || best_diff > tmp_diff) { > - best_rate = tmp_rate; > - best_diff = tmp_diff; > - req->best_parent_rate = parent_rate; > - req->best_parent_hw = parent; > - } > + > + clk_generated_best_diff(req, parent, parent_rate, div, > + &best_diff, &best_rate); > + > > if (!best_diff) > break;